Adding foam for more buoyancy

[addicted2sp33d]

It's Physics Gentlemen.

Dry Pool noodles inside the hull of a SOT kayak do not add bouyancy - they only add weight, though admittedly not very much.

Buoyancy is a measure of how much water your boat displaces, vs the weight of your boat.
"Floating" is where the weight of your boat, matches the weight of the water that you're displacing.
By adding Pool noodles inside your hull, you're not increasing the mass/volume of the displaced water, so you're not adding to the buoyancy.

If you want pool noodles to increase your buoyancy, you need to strap them to the exterior of your hull below the waterline, thereby increasing the volume of displaced water.

In the event that your SOT hull fills with water, the noodles will provide some noticeable buoyancy, but only if your hull takes on a significant volume of water.
By "significant" I mean your hatches are open and a wave came over the top and completely fills your hull.

If your hatches are not all open, there will most likely be a decent volume of air still trapped inside your hull, and that trapped air will provide far more buoyancy than a pool noodle.